Method of and apparatus for drying and storing material



I 0 1,625,451 Aprll 19, 1927 A- B BROWN METHOD OF AND APPARATUS FOR DRYING AND STORIG MATERIAL Filed July 26, 1923 Patented Apr. 19, 1927.

UNITED STATES PATEN l ,1,625,451 T OFFICE.

l.ALFRED BRUCE BROWN, OE CHICAGO, ILLINOIS, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION NEW YORK.

METHOD or AND APPARATUS Foa DRYING AND sToRINe MATERIAL.

,Application led July 26, 1923. Serial No. 653,838.

This invention relates to a method of and ap aratus for drying and storing material. n object of the invention is to remove moisture from material vby the circulation of air of low moisture content in Contact therewith,

Another object is to assist in the heating of material during a drying process 'by circulating air of low moisture content in'contact with the material.

A further object is to remove from the material some of the moisture contained therein by contemporaneously heating the material and circulating air of low moisture .content in contact therewith, removing substantially all of the remaining moisture in the material by. continuing the lheating thereof in a vacuum, and then storing the dried material in the presence of air et low moisture content.

The method .constituting the invention .is especially adapted for drying telephone cables constitutino` a` pluralty of copper conductors, each insu ated with paper tapes and stranded into cable form before the application of a lead sheath to the cable. It is to be understood, however, that the improved method is not limited to thel drying of cable, but may be employed for various other purposes without departing from the spirit and scope of the invention.

It is believed that the improved method will be clearly understood by a description of the apparatus by which it may be performed and the accompanying drawing, Figs. 1 and 2 of which illustrate in diagrammatic form plan and .elevation views respectively of apparatus as utilized'in the drying of a cable of insulated conductors preparatory to the application of a sheath therearoun'd.

Referring to the drawings, a plurality of treating enclosures 10 are associated through openings in the ends 12 thereof with a common receiving or storage enclosure 13, which is provided with a plurality of openings 22 through which cables may be fed from portable reels 25 in the enclosure 13 to a. corresponding number of lead presses23 of any well-known type for applying a lead sheath to the cables. Eachv enclosure 10 is provided with doors 14 and 19 adapted to close openings in ends 11 and 12 respectively thereof, the door 19 being adapted to be maintained in a partially closed position when desired.

An air conditioning apparatus diagrammatically illustrated bythe rectangle 15, and

which may be of any well-known type equipped with a suitable automatic temperature and humidity regulating means, is connected with the enclosure 13 by means of a pipe 3l for continuously supplylng the enclosure 13 with air of low'moisture content. Each of the treating enclosures l0 may be selectively heated by steam, or other suitable heating medium, Howing through pipe coils 2 0 associated therewith. A conduit 17, including a valve 18. also serves to connect each enclosure 10 with a suitable lair pump or blower apparatus 16 which isof the low pressure large volume type for withdrawing air Jfrom the enclosure. An exhaust apparatus (not shown), but which may be of any suitable type, and a source (also not shown) of air dried by chilling or by chemical treatment, are connected to each enclosure 10 by conduits 21 and 30 respectively.

Valves 32 and 33 are included in the conduits 21 and 30 respectively for opening and closing such conduits.

In practicing the method. the cable of paper insulated wire is wound upon a portable reel 25which serves as a take-up reel for the cable stranding machines. A plurality of reels 25 are introduced into an enclosure 10 through the opening formed in the end llthereof by the opening of the door 14, the door-19 atl this time completely closing the opening in the end 12 of Such enclosure 10.l After one of the enclosures 10 has been completely loaded with reels 25 containing the cable to be dried, the door 14 is closed, rendering the enclosure air-tight. The door 19 is then partially opened to provide for a circulation of air between the enclosure 13 and the selected enclosure 10,. The temperature of the enclosure 10 is then raised to approxi- 10 by means of a ump or blower 16 through the passageway 1 the valve 18 being open. Due to the heating of the enclosure 10 b the coils 20, the air circulating therethroug i is raised to ari average temperature of 220 Fahrenheit with a resulting humidity of approximately one per cent as determined :trom a psychrometric chart. This air is brought into contact with the cables on the reels 25 within the enclosure 10 and serves to remove a considerable portion of the moisture in the cablesv and to facilitate' the heating of said cables. After the circulation has been maintained for about three hours, it is stopped by closing the valve 18, and the door 19 is then closed so as to render the end 120i the enclosure 10 air-tight. The absolute pressure in the enclosure 10 is then reduced to that corresponding to one inch of mercury or less by the opening of the valve 32 in the conduit 21, serving to connect the exhaust apparatus which is prefer ably of the large efficiency low volume type with the enclosure 10. It is thus apparent-y that the air pump or blower apparatus 16 serves to withdraw substantially all of the air from the enclosure 10 While the exhaust apparatus connected to the conduit 21 operates to complete the evacuation process. The reduced pressure is maintained'for a period of from three to twenty-one hours, dependent upon the number of conductors comprising the stranded cable. The combined treatment of the cable by heat and vacuum inst described withdraws from the cables on the reels 25 substantially all moisture remaining ofter the first-mentioned period of treatment. Atmospheric pressure is then restored in the enclosure 10 by opening the valve 33 in the conduit 30, thereby admitting air which has been previously dried by chilling or by being chemically treated.

The door 19 is then completelyopened and the reels 25 containing the treated cables are Withdrawn from the enclosure 10 into the enclosure 13 by operators working Within the enclosure. As the various lead presses 23 are in position to receive cables. the cable reels may then be properly positioned before the openings 22 in the enclosure 13 so that the cables may be withdrawn therefrom and passed through the corresponding lead presses 23 which apply lead sheaths thereto. The door 19 is then again completely closed. The valves 32 and 33 are also closed and upon the subsequent opening of the door 14, the particular enclosure 10 which has been emptied is ready to be loaded with a neucharge of reels of cable, the cycle of operations previously described being rc peated during the time the previously treated cables are being sheathed by the presses 23. Each of the enclosures 10 may be operated in the manner described, and upon the completion of the treating of the cables, the reels may be moved therefrom into the common storage chamber 13. It will be noted that at no time are the doors 14 and 19 ofl a particular enclosure 10 contemporaneously in an opened or partially closed position.

Although the air within the enclosure 13 is maintamed at a temperature ranging bctween o Fahrenheit and 110 Fahrenheit, this temperature does not cause serious discomfort to the operators working within the enclosure for the reason that the moisture content of such air is as low as ten per cent. The relation of the size of the enclosure 13 to the amount of air received from the conditioning apparatus 15, and the weight of the cables on the reels 25 is such that when an enclosure 10 is opened and the heated cables on the reels 25 discharged therefrom into the enclosure 13, the temperature in the lat-ter enclosure will not be raised `above the predetermined limit of Fahrenheit. Furthermore, the storage cnclosure, being directly connected with the treating enclosures and being constantly supplied with dry air, it is evident that not only are the cables maintained independent of outside atmospheric humidity conditions throughout the drying process and the storage period,l but also the cables may be stored therein for a considerable length ot time Without introducing any moisture therein. Although, as shown. a plurality of treating enclosures 10 may be used with a single. storage enclosure 13, and a plurality of lead presses 23 maybe supplied from a single Venclosure 13 and the associated enclosures 10. it is evident that this method is not limited to this particular arrangement. since thc enclosures 10 and 13 may be individually associated and a single lead press `employed for such a combination ot' enc'lhsures.

VVhnt. is claimed is: 1. The method of drying material. consisting in depositing the material in an enclosure. circulating air of predetermined moisture content through the enclosure and in contact with the material therein. producing a Vacuum 1n saidenclosurc and then introducing previously dried air into the enclosure to reestablish atmospheric pressure therein.

2. The method of drying material, consisting in depositing the material in an enclosure. circulating air of predetcrn'iined moisture content through the enclosure and in contact.with the material therein. heating the circulating air in said enclosure to a relatively high temperature. and then producing a vacuum in said enclosure.

3'. The method of drying material. consisting in depositing the material in an enclosure. circulating air of low moisture con- `tent through the enclosure and in contact llt! with heating the air in the enclosure to a relatively high temperature, and then producing a high vacuum in the enclosure.

4. 'lhe method of drying material, consisting in depositing'the material in an enclosure, circulating air of low moisture content through the enclosure and in contact with the material, conteniporaneously therewith heating the ail" in the enclosure to a relatively high temperature, producing a high vacuum in the enclosure, and then reestablishing atmospheric pressure in the ericlosure.

5. 'lhe method of drying material, consisting in depositing the material in a .treating enclosure, closing the enclosure, introducing air/o'flow moisture content into the enclosure/from a storage enclosui'e, circulating the introduced air in contact with the material, contemporaneously therewith heating the circulating air to a relatively high temperature, ceasing the introduction into and circulation of air in thetreatmg enclosure, producing a vacuum in the treating enclosure, re-establishing atmos heric pressure in the treating enclosure, an removing the 'material from the treating enclosure into the storage enclosure.

6.' The method of drying material, consisting in de ositing the material in an enclosure, ren fering the interior of the enclosure independent of atmos heric humidity conditions, circulating-ai of low moisture content in contact With the material, conteinporaneously therewith heating the circulating air to a relatively high tempera.- ture, ceasing the circulation of the air, thereafter producing a vacuumin the enclosure,

thereafter re-establishing atmospheric pressure in the enclosure. and storing the dried: material in air of relatively low temperature and low moisture content.

7. The method of dryino' and storing niaterial, consisting in circulating heated air of predetermined moisture content in contact with the material in one enclosure to dry the material, transferring the dried material to a storage enclosure, and'maintanlng the material independent of atmospheric humidity conditions during the drying, transferring and storing thereof.

8. The method of drying and storing material, consisting in circulating heated air of predetermined moisture content in contact with the .material is one enclosure to dry the material, transferring the dried material to another enclosure` and `so maintaining the character of the air in the last-inentioned enclosure that the drying of the material effected by the first-mentioned enclosure is not deleteriously, affected.

9. The method of drying and storing material, consisting in circulating heated air of predetermined moisture content in contact with the material Within one enclosure to remove a portion /of the moisture fron the material, producing a vacuum in the enclosurel to remove the remaining moisture from 'the material, transferring the dried material to another enclosure, and maintaining tlie material yindependent of atmospheric humidity conditions during the transfer thereof.

10. The method of drying cable preparatory to applying sheathing thereto, consisting in depositing the cable in an enclosure, circulating air of low moisture content inl contact with the cable to remove a portion of the moisture from the cable, ceasing the circulation of air, establishing a vacuum in the enclosure to remove substantially all of the remaining moisture in the cable, and

4maintaining the cable in the presence of air of low mo'sture content substantially until the sheath is applied thereto,

11. rl`he method of drying cable preparatory to applying sheathing thereto, consisting in depositing the cable in an enclosure, circulating air of low moisture content. in contact with the cab`e to remove a portion of the moisture from the cable, contemporaneously therewith heating the circulating air, ceasing the circulation of air. establishing a vacuum in the enclosure to remove substantially all of the remaining moisture in the cable, and maintainingthe cable in the presence of air of low moisture Acontent substantially until the sheath is applied thereto.-

12. The method of drying cable preparatory to applying sheathing thereto, consist.-l ing in depositing the cable in an enclosure, circulatingl air of low moisture content in contact with the cable to remove a portion of the moisture from the cable, ceasing the circulation of air, establishing a vacuum in the enclosure to remove substantially all of the remaining moist-.ure in the cable, and

maintaining the cable independent of atmospheric humidity conditions until the sheath is applied thereto.

13. The method of drying cable preparatory to applying a sheath thereto, consisting in circulatingarr of low moisture content in contact therewith and heating the circulating air to a relatively high temperature hun thereby removing a portion of the moisture Y from the cable` producing a vacuum around the cable to remove substantially all of the remainingmoisture tlierefioin, storing the cable in the presence of air of low moisture content until the sheath is applied thereto. and maintaining the cable independent` of atmospheric humidity conditions during the removal of the moisture therefrom. the storage thereof, and the application of the sheath thereto.

14. The method of drying cable preparatory to applying a sheath thereto, consisting in depositing the cable in an enclosure, introducing into the enclosure air having a moisture content of approximately ten per cent and previously heated to a temperature between 100 F. and 110 F., circulating the introduced air through the enclosure and in contact with the cable for approximately three hours, contemporaneously therewith heating the circulating air in the enclosure to an average temperature of 220 F. to reduce the Inoisture content ofthe air one per cent, ceasiner the i11- troduction and circulation of air into and through the enclosure, reducing the pressure within the enclosure to correspond with one inch ot mercury, maintaining the re duced pressure for at least three hours, centeniporaneousl)1 therewith maintaining the temperature of the enclosure at approximately E260 F., and introdiuringr into the cuclosurc previously dried air to rc-establish atmospheric pressure.

l5. The method ot` drying material, consisting in depositing material in an enclosure, introducing into the enclosure air previously heated to a ten'ipcrature between 100I3 F. and 110o F. and having a moisture coutent of approximately ten per cent. contemporaneousl)- therewith heating the enclosure to a temperature of approximately Q6()o l". thereby increasing the temperature ot' the introduced air to approximately 220 l". and reducing the moisture content thereof to one per cent, causing a circulation of the air of increased temperature and reduced moisture content in contact with the material to remove a portion of the moisture therefrom` ceasing the introduction into and the circulation of air through the enclosure, and producing a vacuum in the enclosure for removing substantially all of the re maining moisture from the material.

16. In an apparatus for drying material, two enclosures, one of said enclosures designed so `that it may be closed air-tight, means for establishing communication between the enclosures, means for circulating air of low moisture content through both of said enclosures when they are in communication, means for heating the air in the first-mentioned enclosure. and means for creating a vacuum in said first-mentioned enclosure after it is closed air-tight.

17. In an apparatus for drying material, a storage enclosure, a treatin enclosure adapted to be made air-tight an( having an opening therein through which the material may be introduced thereinto, means for establishing communication between said enclosures for removing the treated materials from said heating enclosure 'and storing them in said storage enclosure, means for circulating air of low moisture content through said enclosure when they are in communication, and means for producing a vacuum in said treating enclosure when it is closed air-tight.

` 18. In an apparatus for dr ing material, a storage enclosure, a treating enclosure adapted to be made air-tight and having an opening therein through which the material may -be introduced thereinto, means for establishing Acommunication bet-Ween said enclosures for removing the treated material from said treating enclosure andstoring it in said storage enclosure, means for circulating air of low moisture content through said enclosures when they are in communication, means for heating the air in said treating enclosure to a relatively high temperature, and means for producing a vacuum in said treating enclosure when it is closed airtight.

In witness whereof, I hereunto subscribe my name this 17th day of July A. D., V1923.

ALFRED BRUCE BROWN. 

